Optimization and process analysis of sunflower oriented seeding device based on CFD-DEM

• A CFD-DEM coupled model for sunflower oriented seeding was established • The optimal parameter combination for oriented seeding was determined • The key mechanisms influencing sunflower oriented seeding were revealed Oriented seeding, as a precise sowing method, ensures the uniform distribution of seeds in the soil, improves germination rate and uniformity, reduces seed waste, optimizes the competition between seeds, and ultimately increases yield per unit area. This study, based on CFD-DEM coupled simulation technology, designs and optimizes a sunflower directional seed metering device, aiming to achieve precise oriented seeding of sunflower seeds. Through the CFD-DEM coupled simulation model, the interaction between the seed and airflow was simulated, and the movement characteristics of the seed were analyzed, along with the effects of key design parameters such as metering tube length, diameter, sowing angle, and inlet negative pressure on sowing performance. Single-factor experiments and rotational orthogonal tests were conducted to analyze the impact of these parameters on sunflower seed movement characteristics. The results of the study show that the optimal parameter combination is a metering tube length of 350 mm, a sowing angle of 30°, a metering tube diameter of 16.5 mm, and an inlet negative pressure of 1960 Pa. Under these conditions, the directional rate of the seed metering device is 84.12%, and the seed spacing coefficient of variation is 4.81%, demonstrating excellent performance. This study provides technical support for sunflower oriented seeding and offers valuable references for the design of seed metering devices for other similar crops.